Restraining device



June 1960 H. 'r. JOHNSTON, JR

RESTRAINING DEVICE 3 Sheets-Sheet 1 Filed April 13, 1959 INVENTOR Howard I doimsoiz, dr.

ATTORNEY June 28, 1960 H. "r. JOHNSTON, JR 2,942,833

RESTRAINING DEVICE Filed April 13; 1959 3 Sheets-Sheet 2 IN VENTOR Howard 7. Jo/msion, J

ATTORNEY June 28, 1960 H. 1'. JOHNSTON, JR 2,942,833

RESTRAINING mavxcxa:

Filed April 13, 1959 3 Sheets-Sheet 3 INVENTOR Howard 7." Ja/ms Z022, Jr".

ATTORNEY United States Patent" "ice 7 2,942,833 REsTR' "Ans To Davies Howard r. Johnstdn,'.1r., Po ughke'epsie, N. assigns, 'to International Business -Machines Corporation, New York, N .Y., a corporation of New York Filed Apr. 13, 1959, sr. N' 805,884 9 Claims. (Cl. 248-356) This invention relates to a novel device which permits free motion in one direction, but restrains motion in the opposite direction unless the force attempting to cause the motion exceeds a predetermined value.

The principal object of this invention is to provide a device which freely changes its length if a nominal force is applied in one direction but will not change its length in the opposite direction unless the force applied inthe opposite direction exceeds a certain predetermined value. Another object of this invention is to provide means for binding two concentric rods to each other only if the force applied to one is in a given direction; but, to automatically release them if this force exceeds a predetermined value. p

A further object of this invention is to provide a release means which is operated when one or more elastic members are caused to contract.

Still another object of this invention is to provide force transfer means which operate release means only if a force applied to the force transfer means is sufiicient to operate one or more elastic members.

Other objects of the invention Will be pointed out in the following description andclaims and illustrated in the accompanying drawings, which disclose; by way of example, the principle of the invention and the best mode which has been contemplated of applying that principle.

the drawings: I p 7 v Fig. 1 isa side view of one embodiment of my invention, with the release means inoperative.

Fig. 2 is the same view as in Fig. -1, except .t'hat the release means are shown operated. I

Fig. 3 is a sectional view taken along line 33-in Fig. 1, showing the binding means. 7 v

Fig. 4 shows the placement of the elastic member-s.

Fig. 5 illustrates another embodiment of my invention.

Figs. 6 and 7a, 7b, 7c illustrate two possible applications of the embodiments of my invention shown in Figs. 15. 7

Referring to Figs. l-4, the numeral 1 refers to a tubular base which is, for convenience, viewed as fixed in position relative to the other portions of the device. A support 2 is comprisedof a shaft 3, a protrusion 5 and "two parallel extensions .7. The protrusion -5 has a hole 6 in it for receiving a release rod '14 which is urged against a pivoted earn 19 by a return spring 16.. Therefore pivoting of the cam 19 from thepositijon shown in Fig. 1 to the position shown in Fig. 2, about pivots 20, causes the release rod 14 to; slide downward within hole .6 against the urging of spring 16. p 7

Each of the two parallel extensions 7 has'an opening 8 .throughwhichopening is placed a :shaft'17 which is urged upward .by two control springs 18 An external force applied to the shaft 17 which is sufficiently large to compress the control springs 18 to the point where the-shaft 17 causes cam 19 to pivot about pivots. 20, will result in a downward operation of the release rod 14 against the ur ing 'of return spring 16. If the external force applied tosh'aft 17 is insiiificientto compress the eoiitrol 's'pn'iig's Patented June 28, 1960 18 to the .point where the shaft 17'causes'cam 19 to pivot, the release rod 14 will not be operated being retained in its original position by the upward urging of return spring 16. I I V V The shaft 3 of support 2 has a number of indentations '4 cut into one'surface. The release rod 14 has an equal number of indentations 15 equally spaced as the indentations 4 on the shaft 3. The purpose of these indentations 4 and 15 is to prevent binding shoes 9 from sliding relative to either the shaft 3 or release rod 14; while, providing a means-for pivoting the binding shoes 9 relative to the'shaft 3 and release rod 14. This action is obtained by disposing the shaft 3 Within the openings 11, and the release rod 14 within the openings 10, of all the binding shoes 9 in such a manner that each binding shoe 9 is restrained from sliding by one indentation 4 and one indentation 15, but is free to pivot relative to both shaft 3 and release rod 14.

The peripheries 12 of all the binding shoes 9 are in contact with the inside surface 13 of the base tube 1. Upward'motion of both the support 2 and the release rod 14 relative to the base tube 1 causes the binding shoes 9 to rotate in a direction which minim'mes frictional engagement between inside surface 13 and the peripheries 12, permitting the support 2 to slide upward freely.

Downward motion of both the support 2 and the release rod 14 relative to the base tube 1 causes the binding shoes 9 to rotate in a direction which increases the frictional engagement between the inside surface 13 and the peripheries 12, until the support 2 is bound to the base tube 1. However, if there is any downward motion of the release rod 14 relative to the support 2 the binding shoes 9 will rotate in the direction which minimizesthe frictional engagement permitting the support 2 to slide downward freely.

Binding shoes 9 may be designed in manydifierent ways. Another example is shown in Fig. 5. The spiral 31 is disposed about release rod' 14 so that the indentations 4 on the shaft 3 of the support 2, and the indentations '15 on the release rod 14 restrain the spiral 31 from sliding relative to either the shaft 3 or release rod 14.

The operation of the device may be summarized as follows: An upward external force on shaft 17 will cause support 2 to move upward, rotating binding shoes 9 in a direction which decreases frictional engagement between inner surface 13 and peripheries 12, allowing the external force to slide the support 2 upward freely. A downward external force on shaft 17 insuflicient to compress control springs 18 to the point where shaft 17 pivots cam 19, will urge support 2 downward. Binding shoes 9 will rotate in a direction which increases frictional engagement between inner surface 13and peripheries 12, prohibiting downward motion of support 2. But, a downward external force on shaft 17 sufficientto compress control springs 18, to the point where shaft 17' pivots cam 19, causes release rod 14 to be moved relative to support 2.. This will cause binding shoes 9 to rotate in a, direction which decreases frictional engagement between inner surface 13 and peripheries 12, permitting the external force 'to move support 2 downward.

The directions spoken of as downwar and upwar are not intended as limitations for the direction of operation of the device may be reversed by turning it upside down, or by moving the base tube 1 relative to the support 2. Similarly, specification of compression-type springs for the control spring 18 not intended to exclude the use of expansion springs for this purpose.

Fig. 6 illustrates one application of the restraining device. A lid 28 is pivoted at pivot 29 in a plane perpendiculart to the plane of motion of the restraining device. The restraining device is pivoted at pivot 30 and shaft '17 is 'pivotalIy attached to bracket 27. Release rod 14 operates whenever the force "applied to the shaft 17 exceeds the I force due to the weight of the lid 28. An operator may V motion of the restraining device. The restraining device is pivoted at pivot 26 and shaft 17 is pivotally attached to br'aoketZl. 'Release rod 14 operates whenever-the force applied to the shaft 17 exceeds'the forcedue to the weight of the plate 22. An operator may lift'or lower the plate 22, but if he lets go it will be -supported by the restraining device as shown in Figs. 7a, 7b and 7c; 'for, the force due to the weight of the plate 22 will not alone operate the release rod 14. Note that the design must be such that the force due to the weight of the plate 22 will always tend to urge it in the direction of the position shown in Fig. 7b' This is obtained if'the pivots 26 and 23 and the shaft 17 are placed as shown in Fig. 7b, so that they will be in a straight line whenever the center-ofgravity C.G. of the plate 22 falls on a line, perpendicular to the'horizon drawn through pivot 23.

A mechanic skilled in the art to which this invention relates may easilyfind more applications for the restraining device. f i

7 While there have been shown and described and pointed out the fundamental novel features of the invention as I V 4 V the cam which moves the release rod relative to the support against the urging of the return spring to unbind the support from the base tube by disengagement of the binding shoes, the control springs being operable only as long as the force due to the external means exceeds a predetermined value.

2. An adjustable device for restraining'a force comprising, a base, support means movable relative to the base by a force due to external means, binding means arranged to bind the support means to the base when the support means are moved in one sense and to unbind when moved in the opposite sense, release means cooperating with the binding means to unbind the support means from the base when the release means are moved in one sense relative to thejsupport means, a shaft associated with the support means, connected to the external means, control springs associated with the shaft in a manner to urge the shaft against the force due to the, external means, a pivoted cam so placed on the support means that operation of the control springs by application to the shaft of the force due to the external means causes the shaft to pivot the cam which moves the release means relative to the support means unbinding the support means from the base by disengagement of the binding means, the control springs being operable only as long'as the force due to the external means exceeds a predetermined value.

3. An adjustable device for restraining a force comprising, a base, support means movable relative to the base by a force due to external means, binding means arranged to bind the support means to the base when the support means are moved in one sense and to unbind when moved in the opposite sense, release means cooperating with the binding means to unbind the support means '1 from the base Whenthe release means are moved in one prising, a circular base tube, a support. consisting of a Ii:

square shaft having one or more indentations on a first face, a protrusion on the first face above the last of the V indentations with a hole parallel'to the shaft and a pair. of parallel extensions of a second'and third face of the support adjacent to the first face above the protrusion 1 with aligned openings in their surfaces, the support being movable relative to the base tube by a force due to external means, one or more fiat binding shoes having first andsecond openings, the peripheries being in frictional engagement with the inside surface of the base tube and base tube when the support is'moved in-one direction and to unbind when the support is moved in the opposite direction, a release'rod slidably mounted through said hole in the protrusion on the support, having one or more regularly spaced indentations disposed within -the 31 second opening in corresponding ones of each binding shoe to restrain their movement along the axis of the release rod, the release rod disengaging the binding shoes which unbind the support from the base tube when the sense relative to the support means, control springs associated with the support means, a pivoted cam so placed on the support means that operation of the control springs by application of the force due to the'external means causes the cam to pivot moving the release means relative to the support means to unbind the support means from the base by disengagement of the binding means, the control springs being operable only as long as the force due to the external means exceeds a predetermined value.

4. An adjustable device for restraining a force comprising, a base, support means movable relative to the base by a force due to external means, binding means arranged to bind the support means to the base when the support means are moved in one sense and to unbind when moved in the opposite sense, release means cooperating with the binding means to unbind the support means from the basewhen the release means'are moved in one sense relative to the support means, control springs as- T- 'sociated with the support means, force transfer means release rod is moved in one direction relative to the support, a return spring associated with the release rod'in a manner to urge the release rod in'the direction that increases the frictional engagement of the binding shoes, a second shaft, placed through the opening in the parallel extensions of the support connected'to the external means,

control springs associated with said second shaft in a manner to urge the shaft against the force due to the external means, a pivoted cam so placed on the parallel extensions of the support that operation of the control springs by application to said second shaft of the force due 'to the external means causes said second shaft to pivot acting upon the release means whenthe control springs operate, operation of the control springs by application of the force due to the external means permitting the force transfer means to cause the release means to move relative to the support means unbinding the support means from the base by disengagement of the binding means, the control springs being operable only as long as the force due to the external means exceeds a predetermined value.

5. An adjustable device for restraining aiforce comprising, a base, support means movable relative to the base by a force due to external means, binding means arranged to bind the support means to the base when the support means are moved in one sense and to unbind when moved in the opposite sense, a release rod slidably mounted on the support means having a number of regularly spaced indentations, disposed with relation to the binding means in a manner restraining movement along the axis of the release rod, the releaserod disengaging the binding means which unbind the support means from the base when the release rod is moved in one direction relative to the support means, a return spring associated with the release rod in a manner to urge the release rod in the direction that increases the frictional engagement of the binding means, elastic means on the support means, force transfer means acting upon the release means when the elastic means operate, the elastic means arranged to operate if the force due to the external means exceeds a predetermined value, the force tranfer means then moving the external means to move the release rod unbinding the support means from the base for as long as the force exceeds the predetermined value.

6. An adjustable device for restraining a force comprising, a base, support means movable relative to the base by a force due to external means, binding means arranged to bind the support means to the base when the support means are moved in one sense and to unbind when moved in the opposite sense, a release rod slidably mounted on the support means having one or more regularly spaced indentations, disposed with relation to the binding means in a manner restraining movement along the axis of the release rod, the release rod disengaging the binding means which unbind the support means from the base tube when the release rod is moved in one direction relative to the support means, elastic means on the support means, force transfer means acting upon the release means when the elastic means operate, the elastic means arranged to operate if the force due to the external means exceeds a predetermined value, the force transfer means then moving the release rod unbinding the support means from the base for as long as the force exceeds the predetermined value.

7. An adjustable device for restraining a force comprising, a base, support means movable relative to the base by a force due to external means, one or more flat binding shoes having peripheries in frictional engagement with the base and the support means in a manner re" raining their movement along the axis of said support means, the binding shoes being arranged to bind the support means to the base when the support means are moved in one direction and to unbind when the support means are moved in the opposite direction, release means cooperating with the binding shoes to unbind the support means from the base when the release means are moved in one sense relative to the support means, elastic means on the support means, force transfer means acting upon the release means when the elastic means operate, the

elastic means arranged to operate if the force due to the external means exceeds a predetermined value, the force transfer means then moving the release means unbinding the support means from the base for as long as the force exceeds the predetermined value.

8. An adjustable device for restraining a force comprising, a base, a support consisting of a square shaft having one or more indentations on a first face, a protrusion on the first face above the last of the indentations with a hole parallel to the shaft and a pair of parallel extensions of a second and third face adjacent to the first face above the protrusion with aligned openings in their surfaces, the support being movable relative to the base tube by a force due to external means, binding means arranged to bind the support means to the base when the support is moved in one sense and to unbind when moved in the opposite sense, release means cooperating with the binding means to unbind the support from the base when the release means are moved in one sense relative to the support, elastic means on the support, force transfer means acting upon the release means when the elastic means operate, the elastic means arranged to operafe if the force due to the external means exceeds a predetermined value, the force transfer means then moving the realse means unbinding the support from the base for as long as the force exceeds the predetermined value.

9. An adjustable device for restraining a force comprising, a base, support means movable relative to the base by a force due to external means, binding means arranged to bind the support means to the base when the support means are moved in one sense and to unbind when moved in the opposite sense, release means cooperating with the binding means to unbind the support means from the base when the release means are moved in one sense relative to the support means, elastic means on the support means, force transfer means acting upon the release means when the elastic means operate, the elastic means arranged to operate if the force due to the external means exceeds a predetermined value, the force transfer means then moving the release means unbinding the support means from the base for as long as the force exceeds the predetermined value.

References Cited in the file of this patent UNITED STATES PATENTS 2,411,481 Tykeson Nov. 19, 1946 

